Pipenv Cloud Native Buildpack

The Paketo Pipenv Buildpack is a Cloud Native Buildpack that installs pipenv into a layer and makes it available on the PATH.

The buildpack is published for consumption at gcr.io/paketo-buildpacks/pipenv and paketocommunity/pipenv.

Behavior

This buildpack always participates.

The buildpack will do the following:

At build time:
- Contributes the pipenv binary to a layer
- Prepends the pipenv layer to the PYTHONPATH
- Adds the newly installed pipenv location to PATH
At run time:
- Does nothing

Configuration

Environment Variable	Description
`$BP_PIPENV_VERSION`	Configure the version of pipenv to install. Buildpack releases (and the pipenv versions for each release) can be found here.

Integration

The Pipenv CNB provides pipenv as a dependency. Downstream buildpacks, can require the pipenv dependency by generating a Build Plan TOML file that looks like the following:

[[requires]]

  # The name of the Pipenv dependency is "pipenv". This value is considered
  # part of the public API for the buildpack and will not change without a plan
  # for deprecation.
  name = "pipenv"

  # The version of the Pipenv dependency is not required. In the case it
  # is not specified, the buildpack will provide the default version, which can
  # be seen in the buildpack.toml file.
  # If you wish to request a specific version, the buildpack supports
  # specifying a semver constraint in the form of "2018.*", "2018.11.*", or even
  # "2018.11.26".
  version = "2018.11.26"

  # The Pipenv buildpack supports some non-required metadata options.
  [requires.metadata]

    # Setting the build flag to true will ensure that the Pipenv
    # depdendency is available on the $PATH for subsequent buildpacks during
    # their build phase. If you are writing a buildpack that needs to run Pipenv
    # during its build process, this flag should be set to true.
    build = true

    # Setting the launch flag to true will ensure that the Pipenv
    # dependency is available on the $PATH for the running application. If you are
    # writing an application that needs to run Pipenv at runtime, this flag should
    # be set to true.
    launch = true

Limitations

This buildpack requires internet connectivity to install pipenv. Installation in an air-gapped environment is not supported.

Usage

To package this buildpack for consumption:

$ ./scripts/package.sh --version x.x.x

This will create a buildpackage.cnb file under the build directory which you can use to build your app as follows: pack build <app-name> -p <path-to-app> -b <cpython-buildpack> -b <pip-buildpack> -b build/buildpackage.cnb -b <some-pipenv-consumer-buildpack>.

To run the unit and integration tests for this buildpack: